Unless you have poked a hole or have a crack in the ama, the bungee cord recess is broken, or the handle attachment is bad, then the screw-in plug open is the source. I never unscrew that plug. I do not get water in my amas.

Open up the drain plug, drain all water, and clean the plug really well of sand or other debris and check the rubber ring, then tighten up good and try again. If you still get water in, there's probably a puncture or crack somewhere.

I was told to unscrew the plug as the pressure builds in the heat and can split/burst the ama?

I was told by the Hobie dealer who sold me the AI to undue the bungs after all trips, as they sold a few AI's in Turkey and they had no end of probs with amas splitting...........

And I'll have you know it went up to a staggering 20c in the sun today seriously I have a RIB boat, and in the heat the tubes swell by at least 25% unless I let air out, if left the seems will split........

... a staggering 20c in the sun today seriously I have a RIB boat, and in the heat the tubes swell by at least 25% unless I let air out, if left the seems will split........

Crikey mate, don't think they'd sell many of those RIBs in Oz... tubes swelling by 25% in 20c??? We get that on a warmish winter's day! As to the splitting [non] issue, I've no doubt that on a hot day, left in the Aussie summer sun, the internal temp of the hull and pontoons could reach as high as 45C, maybe even 50c. Haven't heard of any explosions from Aussie owners, so I think you'll be OK.